This invention relates to an improved retaining wall and more particularly to an anchor or tie back wall.
Retaining walls generally constitute a vertical support barrier for an earthen embankment. The forces of the embankment on a vertical retaining wall can be calculated in view of the characteristics of the earthen material being retained and the height of the wall. Such calculations enable engineers to design a particular type of retaining wall. That is, the design and construction of various retaining walls depends upon the materials utilized to make the wall and the particular construction technique involved.
For example, a typical retaining wall may be made of reinforced concrete cast in place. Typically for a cast in place wall, a large concrete pedestal is cast at the base of the wall having an extension which projects into or underlies the embankment that is to be retained. An integral upstanding, vertical wall is cast on the base. The dimensions and other characteristics of such cast in place wall can be determined using standard or known engineering techniques.
Another type of retaining wall is base on earth reinforcement techniques as disclosed in Vidal, U.S. Pat. No. 3,421,326 entitled "Constructional Works" and Vidal, U.S. Pat. No. 3,686,873 entitled "Constructional Works". This type of retaining wall is designed in accord with techniques and methods developed by Vidal.
Yet another type of retaining wall is known as an anchor wall or a tie back wall. With an anchor wall, vertical members that support the wall are maintained in place by anchors which are attached to the members and extend back into the earthen embankment. Various types of cross members are connected to the vertical members to form a total wall structure. Again the design dimensions of this type of wall can be calculated using known civil engineering techniques.
A particular type of anchor wall which has been constructed requires, as a first step, drilling of vertical passages or holes along a line defining the wall. Reinforced concrete posts are then cast into these vertical passages. The earth is then stripped away from one side of the vertical posts. As the earth is stripped from one side of the posts, the vertical posts are anchored into position by means of anchors through the posts into the remaining earthen embankment. Thus, as the earth is stripped away from one side and anchors are attached and fastened into the earthen embankment, a facing of the earthen embankment is exposed defined generally by the line of the wall. It is then possible to put cross members between the vertical posts to retain the earth. For example, the reinforced concrete posts may be connected by a cast in place panel.
Though such an anchor wall is very useful and the design dimensions for such a wall can be calculated using known techniques, there has remained a need and desire to provide a more efficient wall of this general type which utilizes fewer caissons or vertical posts per unit length of wall and which may be easily and quickly constructed at a construction site with a minimum amount of casting necessary at that site.